When netizens voted for the beauty queen "Chun Chun" (Li Yuchun) to apply thick moisturizer to their fair and pink skin frequently, it was a painful time for the friends engaged in corrugated packaging. In this dry season, doing a good job of carton moisturizing care has become the top priority for managers at all levels. And don't complain about the carton customers being too picky, the carton burst line is really unsightly. If you are invited by a client to go to heaven and earth, you will never choose a beautiful woman to accompany!
The friends of the carton factory are busy on weekdays, just for "cartons are beautiful, goods and customers' homes". If the cartons delivered to the customers are all perfect, it is difficult for lustful customers to like it or not. Below, the "Packaging Zone" micro-edited the 12 major "skin care methods" for dry weather corrugated boxes in detail.
1. Pretreatment of base paper
Usually, the root cause of carton bursting is that the cardboard is too dry and the folding resistance drops sharply. Therefore, maintaining a reasonable moisture content before the raw paper is put on the line is the fundamental way to solve the problem of thread bursting. This office mainly starts with the moisture retention of base paper and the choice of base paper.
1. The moisturizing of the cardboard is the key to solving the burst.
Experiments have shown that in the dry season, if it is the best wood pulp kraft box paper with the best folding resistance, if the moisture is less than 6%, it is easy to produce cracking; if the liner board paper with the most short fiber pulp recycled, the moisture It is better to be no less than 8%. If it is an environmentally friendly cardboard made from 100% recycled pulp, the moisture content is preferably above 9%.
The most fundamental way to solve the carton drying and explosion line is to ensure that the moisture content of the roll paper before loading on the machine is in a reasonable state. Generally speaking, the moisture content of the base paper when it leaves the factory is usually between 8-10%. If the moisture content of the base paper warehouse is less than 50%, the base paper will lose moisture and produce thread burst. Therefore, in dry weather, the base paper warehouse may wish to be humidified. It is recommended to use a humidifier to humidify the base paper warehouse in the dry season, and the relative humidity of the warehouse should be maintained at 65-75% RH.
In addition, in order to ensure the relative humidity of the storage environment, it is recommended that the base paper warehouse be isolated from the outside world, such as closed doors and windows, and the addition of transparent soft rubber curtains.
2. Choose coated white cards with different fold resistance according to different cardboard and water content
For some double corrugated boxes with 150g / sqm or 180g / sqm high watts, when the crimp is bent at the crimping line, the tissue is subject to particularly high tensile strength, which is prone to bursting. For this type of carton, it is not easy to solve by increasing the moisture alone, and it is necessary to purchase some box paper or coated whiteboard with higher folding resistance. For example, VISY and SMURFIT STONE which use all wood pulp. If the facial paper is a coated whiteboard with offset printing, a white card with a cow bottom can be used.
2. Corrugated Cardboard Line processing
3. Add spray device to spray the cardboard
The purpose of this method is to increase the moisture of the cardboard paper by spraying it on the surface. When the line speed of the tile is very fast, its effect is weakened, but it is also an effective improvement method.
4. Directly coat the cardboard with a layer of water
A coating device can be installed between the raw paper support of the tile line and the preheating cylinder. When the weather is dry, the base paper with low moisture content is specially humidified. This device humidifies the base paper better than spray, but the cost is about 10,000 yuan.
5. Spraying and humidifying before slitting and slitting
When the corrugated cardboard passes through the slitting and creasing machine, if the inner paper is too dry, micro-cracks may be formed after the creasing wheel is crimped. At first glance, there is no bursting phenomenon, but if you bend it, you can see the cracks. Therefore, some manufacturers install a spray device or wet water device in front of the slitting machine to improve the problem of thread burst.
6. The pressure roller is covered with a layer of sponge tape, which is said to have a very good effect.
Usually during the dry season, the operator of the tile cutter will check whether the upper and lower crimping wheels are correctly positioned. Pre-press the cardboard before the crimping and change to double crimping and other measures. But these are not enough to solve the problem of bursting. At this time, we can wrap a round of sponge tape on the crimping wheel to make the die-cutting board, or glue it with glue. Practice has proved that the application of sponge rubber strips is helpful to buffer and evenly disperse the instantaneous pressure of the cam, and has a very obvious effect on solving the paper micro-cracks in the crimping position.
7. Reasonably change the paper distribution of corrugated cardboard, but also help you save paper costs.
Many cartonboards improve their moisture resistance by surface sizing. However, in dry weather, you may wish to use low-surface sizing paper as the liner paper, on the one hand, it is beneficial to absorb the moisture in the spray device and glue, on the other hand, it can also reduce the cost of paper. Generally, the cost of re-sizing the surface of the cardboard paper and that of the unsizing ton paper are 100-300 yuan.
3. Post-processing of tile line
8. Spray the entire corrugated board
In dry weather, the moisture of corrugated cardboard is easy to be lost. At this time, after stacking the corrugated cardboard, spray water vapor against the corrugated gap, which will help the back-end mounting pit and die cutting. But it can not solve the problem of corrugated cardboard bursting on the tile line and the horizontal line.
9. When the colored paper is glazed, install a water cooling device in the drying tunnel to avoid excessive evaporation of water
Colored paper is easy to lose moisture when glazed and dried. You can use a large-diameter exhaust duct and install a water cooling device on the drying tunnel to avoid over-drying and brittleness of the colored paper during drying and curing.
10. The wet water roller of the automatic paper Laminating Machine with water sends the die cutting indentation line burst
Under normal circumstances, the moisture content of cardboard after mounting colored paper can reach more than 10%. However, when the weather is high and dry and the moisture content of the cardboard to be mounted is very low, the moisture of the glue quickly evaporates, and the moisture of the cardboard that is mounted is still very low, causing a burst line at the die-cutting indentation. At this time, you may wish to use the wet water roller of the self-mounting machine to wet the water on the back of the cardboard. At the same time, select the glue with low solid content and increase the amount of glue.
11. Wet the colored paper or corrugated board with a printing machine.
For color pages that are printed but burst when folded, a single-color offset press can be used to print the water on the back. For corrugated cardboard with slotted blasting or die cutting blasting, a large solid plate can be installed on the flexo printing machine to print water on the corrugated cardboard.
12. Humidify the water sponge on the automatic paste box machine
When bonding on the glue box machine, a water tank can also be installed under the Conveyor Belt of the glue box machine. Two wet water sponges are placed at the corresponding positions of the vertical pressure line of the cardboard in the water tank, so that the cardboard absorbs water before achieving the longitudinal pressure line 180 degrees Fold to prevent the paper from bursting under the longitudinal pressure line.
